Re: [SQL] Fw: Whats happen here?

Try this:

drop function char_eq_varchar(bpchar,varchar);
create function char_eq_varchar(bpchar,varchar) returns bool as
'
declare
i2 text;
i1 text;
begin
i1:= trim($1);
i2:= $2;
if i1 = i2 then
return TRUE;
else
return FALSE;
end if;
end;
' language 'plpgsql';

drop operator = (bpchar,"varchar");
create operator = (
leftarg=bpchar,
rightarg="varchar",
procedure=char_eq_varchar,
commutator='=',
negator='<>',
restrict=eqsel,
join=eqjoinsel
);

drop table x;
drop table y;
create table x(a char(20));
create table y(a varchar(5));
insert into x values('a');
insert into y values('a');
select * from x, y where x.a = y.a;
a |a
--------------------+-
a |a
(1 row)

Jose'

Nikolay Mijaylov ha scritto:

> > Whats happen here?
> > -------------------------
> >
> > root=> \dt
> >
> > Database = root
> > +------------------+----------------------------------+----------+
> > | Owner | Relation | Type |
> > +------------------+----------------------------------+----------+
> > | root | x | table |
> > | root | y | table |
> > +------------------+----------------------------------+----------+
> > root=> \d x
> >
> > Table = x
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > | Field | Type |
> > Length|
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > | a | char() |
> > 20 |
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > root=> \d y
> >
> > Table = y
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > | Field | Type |
> > Length|
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > | a | varchar() |
> > 5 |
> >
> +----------------------------------+----------------------------------+-----
> > --+
> > root=>select * from x a, y b where a.a = b.a;
> > ERROR: There is more than one possible operator '=' for types 'bpchar'
> and
> > 'varchar'
> > You will have to retype this query using an explicit cast
> >
> >
> >
> > root=> select * from x a, y b where text(a.a) = text(b.b);
> >ERROR: There is more than one possible operator '=' for types 'bpchar' and
> 'varchar'
> > You will have to retype this query using an explicit cast
> >
> > --------------------------------------------------------------
> > The reboots are for hardware upgrades!
> > "http://www.nmmm.nu; <nmmm(at)nmmm(dot)nu>
> >
> >
>
> ************